Rolling Your Own TiVo WiFi Adapter

October 14, 2020 by 16 Comments

The only thing more surprising than finding out TiVo actually put out a new 4K set-top box recently is learning that somehow they didn’t bother to build WiFi into the thing. You’re forced to buy a special wireless adapter to the tune of $60 USD to add the feature. We’d make a joke about the company living in the past, but frankly, it would be too easy.

Having to buy just one of these expensive dongles in 2020 would be insulting enough, but TiVo superfan [xxbiohazrdxx] needed four of them. Rather than hand nearly $250 to the antennae-headed overlords, they decided to reverse engineer the adapter and produce their own low-cost version. While the final result might not be as slim and svelte as the original, it does come in at less than 1/4 the price.

Operating under the assumption that the TiVo would only talk to a WiFi adapter based on the same Broadcom BCM43569 chipset used in the official one, [xxbiohazrdxx] started by trying to find a standard USB dongle that might be a drop-in replacement. Unfortunately, it looks like this particular chip was almost exclusively used in proprietary applications, most commonly as a WiFi board inside of smart TVs. But as it turns out, that wasn’t necessarily a deal breaker.

After some searching, [xxbiohazrdxx] eventually found the promising CyberTAN NU361-HS board. Not only was it based on the right chipset and ran from 5 volts, but its FCC ID entry had a complete pinout for the connector. This particular WiFi module is used in a number of budget TVs and is widely available as a spare part for less than $10. By combing the board and a USB breakout PCB inside of a 3D printed case, you’ve got a plug-and-play WiFi adapter that the TiVo thinks is the real deal.

There was a time when Hackaday was flooded with TiVo hacks, but it’s now been more than a decade since cheap carrier-provided DVRs ate the company’s lunch. Realistically, there’s an excellent chance that this post will be the only time a mention of the once-mighty DVR graces the front page in 2020. While the reign of the TiVo might be at its end, the impact it had as one of the first Linux-powered consumer devices will be etched in hacker history forever.

Designing And Building A Custom Optical Fuel Sensor

October 14, 2020 by 36 Comments

At some time or another, we’ve all had an idea we thought was so clever that we jumped on the Internet to see if somebody else had already come up with it. Most of the time, they have. But on the off chance that you can’t find any signs of it online, you’re left with basically two possible conclusions. Either you’re about to enter uncharted territory, or your idea is so bad that everyone has collectively dismissed it already.

Which is precisely where [James Stanley] recently found himself. He had an idea for an non-contact optical sensor which would detect when his racing mower was about to run out of gas by analyzing light passed through a clear section of fuel hose. He couldn’t find any previous DIY examples of such a device, nor did there appear to be a commercial version. But did that mean it wouldn’t work, or that nobody had ever tried before?

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Cheap All-Sky Camera Is Easy As Pi

October 14, 2020 by 28 Comments

Combining a Raspberry Pi HQ camera and a waterproof housing, [jippo12] made an all-sky, all-Pi meteorite tracking camera on the cheap, and it takes fantastic photos of the heavens. It’s even got its own YouTube channel. Inside there’s a Raspberry Pi 4 plus an HQ camera to take the pictures. But there’s also a system in place to keep everything warm and working properly. It uses a Raspberry Pi 3+, a temperature sensor, and a relay control HAT to pump pixies through a couple of 10 W resistors, making just enough heat to warm up the dome to keep it from fogging.

A few years ago, we reported that NASA was tracking meteorites (or fireballs, if you prefer) with a distributed network of all-sky cameras — cameras with 360° views of the night sky. Soon after, we found out that the French were doing something quite similar with their FRIPON network. We pondered how cool it would be to have a hacker network of these things, but zut alors! Have you seen the prices of these things?  Nice hack, [jippo12]!

Rather do things the old fashioned way? Dust off that DSLR, fire up that printer, and check out OpenAstroTracker.

Linux Fu: Global Search And Replace With Ripgrep

October 14, 2020 by 9 Comments

If you are even a casual Linux user, you probably know how to use grep. Even if you aren’t a regular expression guru, it is easy to use grep to search for lines in a file that match anything from simple strings to complex patterns. Of course, grep is fine for looking, but what if you want to find things and change them. Maybe you want to change each instance of “HackADay” to “Hackaday,” for example. You might use sed, but it is somewhat hard to use. You could use awk, but as a general-purpose language, it seems a bit of overkill for such a simple and common task. That’s the idea behind ripgrep which actually has the command name rg. Using rg, you can do things that grep can do using more modern regular expressions and also do replacements.

A Note on Installing Ripgrep

Your best bet is to get ripgrep from your repositories. When I tried running KDE Neon, it helpfully told me that I could install a version using apt or take a Snap version that was newer. I usually hate installing a snap, but I did anyway. It informed me that I had to add –classic to the install line because ripgrep could affect files outside the Snap sandbox. Since the whole purpose of the program is to change files, I didn’t think that was too surprising, so I did the install.

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Homebrew Pulsejet Uses Carbon Fiber To Great Effect

October 14, 2020 by 21 Comments

Jet engines are undeniably awesome, but their inherent complexity prevents many from experimenting with the technology at home. Perhaps the most accessible design is the pulsejet; in valveless form, it can be built relatively easily without needing a lot of precision spinning parts. [Integza] decided to try building his own, facing many hurdles along the way. (Video, embedded below.)

Despite eschewing turbines and compressors, and consisting of just an intake, exhaust and a combustion chamber, the pulsejet still presents many challenges to the home gamer. Primary concerns are sustaining combustion without the jet flaming out, and building the jet out of suitable materials that won’t simply melt into a gooey puddle on the floor.

[Integza]’s design process began with many 3D-printed attempts. While the geometry was on point, none of these designs could run for more than a few seconds without melting and falling apart. Determined to avoid the typical welded-steel approach, [Integza] instead resolved to go left-of-field with carbon fibre mat combined with high-temperature sealant. With the help of a 3D-printed mold, he was able to produce a working engine that could stand up to the high temperatures and produce that glorious pulsejet sound.

It’s come a long way from [Integza]’s earlier experiments, and we look forward to seeing where it goes next – whether that be on a plane or perhaps even a go-kart. Video after the break.

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Lowering The Bar For Exam Software Security

October 14, 2020 by 24 Comments

Most standardized tests have a fee: the SAT costs $50, the GRE costs $200, and the NY Bar Exam costs $250. This year, the bar exam came at a much larger cost for recent law school graduates — their privacy.

Many in-person events have had to find ways to move to the internet this year, and exams are no exception. We’d like to think that online exams shouldn’t be a big deal. It’s 2020. We have a pretty good grasp on how security and privacy should work, and it shouldn’t be too hard to implement sensible anti-cheating features.

It shouldn’t be a big deal, but for one software firm, it really is.

The NY State Board of Law Examiners (NY BOLE), along with several other state exam boards, chose to administer this year’s bar exam via ExamSoft’s Examplify. If you’ve missed out on the Examplify Saga, following the Diploma Privilege for New York account on Twitter will get you caught up pretty quickly. Essentially, according to its users, Examplify is an unmitigated disaster. Let’s start with something that should have been settled twenty years ago.

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Tiny Mario Clone On A Tiny Processor

October 14, 2020 by 8 Comments

We’ve become used to seeing retro games running on commodity microcontrollers where once they would have required the bleeding-edge console hardware of their day. [Duncan]’s Mario clone takes the genre a little further, using not a processor with plenty of pins for peripherals, but instead the humble ATtiny85. Its eight pins drive two OLED displays, and accept input from the buttons of a cheap Nintendo-like controller.

The write-up is split between software and hardware sections, with all the software itself available from a GitHub repository. He’s bit-banging the i2C for the displays for an impressive turn of speed, and the ATtiny’s lack of pins is addressed by clever use of resistive dividers to present a different voltage for each button pressed. With a truth table of voltages he’s even able to detect multiple simultaneous button presses. Music is achieved with the chip’s limited resources by storing the sounds in EEPROM, and clocked it at 16 MHz for smooth gameplay.

The whole is mounted inside the shell of the controller, with its USB guts removed and replaced by a smart custom PCB. An unexpected problem with ground plane fill caused a temporary roadblock reading the buttons, but the finished product is a very Nintendo-like experience. We like it.